Functional Evolution of Locomotor Posture in Tetrapods

四足动物运动姿势的功能进化

• 批准号: 0080158
• 负责人: Stephen Reilly
• 金额: --
• 依托单位: Ohio University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2004-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0080158&HistoricalAwards=false
• 关键词: Functional; Evolution; Locomotor; Posture; Tetrapods

The early terrestrial vertebrates are thought to have had a sprawling posture, as do modern salamanders, where the limbs are held laterally to the body. Erect posture, where the limbs are held directly under the body, is thought to have evolved twice, once in the ancestors of mammals and once in the lineage containing dinosaurs (archosaurs). The biomechanical consequences of these different postures have been little studied and the hypothesis of a three-grade postural system (sprawling, semi-erect, and erect postures) has been recently questioned. A quantitative understanding of locomotor posture in living tetrapods with different postures is necessary to evaluate the consequences of this postural shift in the evolution of terrestrial tetrapods. The general goal of this study is to complete functional morphological analyses of hind limb kinematics and whole body kinetics (ground reaction forces and external mechanical work) during locomotion in a series of extant taxa representative of each major tetrapod class. These data will then be used to define, compare, and contrast various tetrapod postures in order to test a series of hypotheses about postural function and evolution in vertebrates. They will also be used to determine whether and how force dynamics of the limbs have changed during the evolutionary shift from sprawling to erect postures.

早期的陆生脊椎动物被认为有一种伸展的姿势，就像现代的蝾螈一样，四肢与身体保持横向。直立的姿势，即四肢直接放在身体下面的姿势，被认为已经进化了两次，一次是在哺乳动物的祖先身上，一次是在包含恐龙（祖龙）的谱系中。这些不同姿势的生物力学结果很少被研究，最近关于三等级姿势系统（伸展、半直立和直立）的假设受到质疑。定量了解不同姿势的四足动物的运动姿势对于评估这种姿势变化在陆生四足动物进化中的影响是必要的。本研究的总体目标是完成具有代表性的现存四足动物类群在运动过程中的后肢运动学和全身动力学（地面反作用力和外部机械功）的功能形态学分析。然后，这些数据将用于定义、比较和对比各种四足动物的姿势，以测试关于脊椎动物姿势功能和进化的一系列假设。它们还将用于确定四肢的力动力学是否以及如何在从伸展到直立的进化过程中发生变化。